On Wed, Feb 01, 2017 at 09:33:51AM -0500, Mike Snitzer wrote: > > FYI, what we do both in the XFS buffer cache and the new direct I/O > > code is to use a > > > > cmpxchg(&dio->error, 0, ret); > > > > in a similar situation, which should work here, too. > > What is the benefit? Faster than the conditional? In the cases where I added the code the concern is that multiple bio completions could race updating the flag, cmpxchg is a good protection against that. I'll need to take a look at the dm case Eric reported in more detail to comment on it, though. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
